Projectile.



G. F. COOMBER.

PROJECTILE. APPLICATION man ocT.19.1915.

1,181,849. Patentd m 2,- 1916.

Wifncooo GEORGE F. coommn, or KANSAS cm, mssoom.

rnomcrmn.

Specification of ELetters Patent.

' Patented Ma 2, 1916 Application filed October 19, 1915. Serial m. 56,758.

To all whom it may concern:

Be it lmown that L-Gnoncn F; Coo BnR, a citizen of the United States, residing'at Kansas City, in the county of Jackson and State of Missouri, have invented certain new and useful Improvements in Projectiles; and I do hereby declare the following to be a full,

clear, and exact description of the invention, such as will enable others skilled in the art to'which it appertains to make and use the same.

My invention relates to new and useful improvements in projectiles of that class to be used in connection with fire arms, cannon and the like, and'my object is to provide means for causing the rojectile to spin or rotate after leaving the ore of the fire arm. And a further object is to so construct the projectile as to snugly fit the bore of the fire arm to prevent the force of the powder from I passing around the projectile.

Other objects and advantages will be hereinafter set forth, and more particularly pointed out in the accompanying specification.

In the accompanying drawings which are made apart of this application, Figure l is a perspective view of the projectile; Fig. 2 is aside elevation thereof, and Fig. 3 is a rear end elevation.

Referring to the drawings in which similar reference numerals designate corresponding parts throughout the several views,1 indicates the projectile, the forward end of which is tapered in the usual manner and said forward end is priwided with a plurality of spirally arranged grooves 2' which trend lengthwise of the projectile and 3'i'nd1- cates ribs at the rear end of the projectile formed by cutting away portions of the body of the projectile, said ribs likewise extending spirally of the projectile and lengthwise thereof.

The grooves-and ribs occupy substantially two-thirds the length of the projectile,

thereby leaving a solid portion 4: between the spiral grooves and ribs, said solid portion being designed to fill the bore of the fire arm in which the projectile is used to prevent the force of the powder or gases from.

escaping from the bore of the firearm around the projectile. j I

By constructing the projectile in this man ner, it is not necessary to provide the usual rifling Within the bore of the fire arm as the grooves at the forward end of the projectile andthe ribs at the rear end thereof willcause the projectile to rapidly rotate after leaving the bore of the firearm. It will likewise be seen that by providing the spirally arranged grooves in the forward end of the projectile, a greater rotating force will be imparted to the projectile than would be 0btained with the use of the ribs alone, as the-- I pressure of the air is greater at the forward end of the projectilethan at the rear end. It will likewise be understood that if desired, the spiral trend of the grooves and ribs may be either to the right orleft as occasion may require.

The. improved rotation causing increased gyroscopic action will tend to cause'the more direct course of the projectile to the end of its flight.

Havin thus fully described my invention what I c aimas new and desireto secure by.

Letters Patent. of the United States, is':--

A projectile for firearms having spirally arranged grooves at its forward end and spirally arranged ribs at its rear end, said ribs being tangentially arranged to-the axis of the projectile, the rear ends oftthe ribs extending from the axial center of the pros.

- jectile to the outer periphery thereof, said ribs decreasing in depth from their rear to their forward ends, said grooves and' ribs being separated by a solid diameter of the projectile.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

GEORGE F .COOMBER.

' Witnesses: i

' JAMES F. REED,

DENNIS R. MCDERMOTT.

Copies of this patent may be obtaini for live cents each, by addressing the (maintainer of Washington, D. 0.

portion the full 

